Real-time sowing-rate detection for rapeseed precision planter using microwave resonant cavity perturbation technology with absorptive damping - Xianfeng Yang; Yinyan Shi; Xiaochan Wang; Xuekai Huang; Lei Wang; Xiaolei Zhang; Enlai Zheng; Guoxiang Sun; Xiaojun Gao (Computers and Electronics in Agriculture, 2026)